Part 3 (1/2)

Following these principles, we have, after Mr Macquer's exa arranged the numerous class of elastic aerifor only atmospheric air _Gas_, therefore, in our noree of saturation in any body with caloric; being, in fact, a teruish each species of gas, we employ a second term from the name of the base, which, saturated with caloric, foras Thus, we name water combined to saturation with caloric, so as to foras_; ether, coas_; the coas_; and, following the saas_, and so on of every substance susceptible of being coasseous or elastic aeriform state

We have already seen, that the atasses, or aeriform fluids, one of which is capable, by respiration, of contributing to animal life, and in which metals are calcinable, and combustible bodies may burn; the other, on the contrary, is endoith directly opposite qualities; it cannot be breathed by animals, neither will it admit of the combustion of inflaiven to the base of the foren_, fronor_; because, in reality, one of the eneral properties of this base is to for with many different substances The union of this base with caloric we teras_, which is the same as foras, at the temperature of 10 (5450), and under a pressure equal to 28 inches of the barorain for each cubical inch, or one ounce and a half to each cubical foot

The chemical properties of the noxious portion of at hitherto but little knoe have been satisfied to derive the na such ani it the name of _azote_, from the Greek privitive particle [Greek: a] and [Greek: xae], vita; hence the naas_; the weight of which, in the saros and 48 grs to the cubical foot, or 04444 of a grain to the cubical inch We cannot deny that this name appears somewhat extraordinary; but this must be the case with all new terms, which cannot be expected to beco endeavoured to find a nation without success; it was at first proposed to call it _alkaligen gas_, as, from the experiments of Mr Berthollet, it appears to enter into the composition of ammoniac, or volatile alkali; but then, we have as yet no proof of itsone of the constituent elements of the other alkalies; beside, it is proved to coood reason to have called it _nitrigen_ For these reasons, finding it necessary to reject any name upon systematic principles, we have considered that we run no risk of as_, which only express a matter of fact, or that property which it possesses, of depriving such animals as breathe it of their lives

I should anticipate subjects more properly reserved for the subsequent chapters, were I in this place to enter upon the noasses: It is sufficient, in this part of the work, to establish the principles upon which their denominations are founded

The principal merit of the nomenclature we have adopted is, that, when once the siuished by an appropriate term, the names of all its compounds derive readily, and necessarily, frolish, the word _steam_ is exclusively appropriated to water in the state of vapour E

CHAP V

_Of the Decoen Gas by Sulphur, Phosphorus, and Charcoal--and of the For experiht never to be deviated from, that they be simplified as much as possible, and that every circu their results complicated be carefully removed Wherefore, in the experiments which form the object of this chapter, we have never employed atmospheric air, which is not a sias, which forms a part of itscombustion and calcination; but, besides that it retards these operations very considerably, we are not certain but it may even alter their results in soht it necessary to re use of pure oxygen gas in the following experias; and I shall advert to such differences as take place in the results of these, when the oxygen gas, or pure vital air, isfilled a bell-glass (A Pl iv fig 3), of between five and six pints h, where it was filled, into the quicksilver bath, bydried the rains of Kunkel's phosphorus in two little China cups, like that represented at D, fig 3 under the glass A; and that I ht set fire to each of the portions of phosphorus separately, and to prevent the one fro fire from the other, one of the dishes was covered with a piece of flat glass I next raised the quicksilver in the bell-glass up to E F, by sucking out a sufficient portion of the gas by means of the syphon G H I After this, by16), made red hot, I set fire to the two portions of phosphorus successively, first burning that portion which was not covered with the piece of glass The combustion was extremely rapid, attended with a very brilliant flaht and heat In consequence of the great heat induced, the gas was at first much dilated, but soon after the mercury returned to its level, and a considerable absorption of gas took place; at the salass becaht flakes of concrete phosphoric acid

At the beginning of the experias, reduced, as above directed, to a common standard, amounted to 162 cubical inches; and, after the combustion was finished, only 23-1/4 cubical inches, likewise reduced to the standard, re the corains

A part of the phosphorus re washed on purpose to separate the acid, weighed about 16-1/4 grains; so that about 45 grains of phosphorus had been burned: But, as it is hardly possible to avoid an error of one or two grains, I leave the quantity so far qualified Hence, as nearly 45 grains of phosphorus had, in this experiravitating ht to conclude, that the weight of the substance resulting from the combustion in foren erains And we shall presently find, that these flakes consisted entirely of a solid or concrete acid When we reduce these weights to hundredth parts, it will be found, that 100 parts of phosphorus require 154 parts of oxygen for saturation, and that this combination will produce 254 parts of concrete phosphoric acid, in form of white fleecy flakes

This experi en possesses a stronger elective attraction, or affinity, for phosphorus than for caloric; that, in consequence of this, the phosphorus attracts the base of oxygen gas fro set free, spreads itself over the surrounding bodies But, though this experiment be so far perfectly conclusive, it is not sufficiently rigorous, as, in the apparatus described, it is iht of the flakes of concrete acid which are for the weights of oxygen and phosphorus employed; but as, in physics, and in chemistry, it is not allowable to suppose what is capable of being ascertained by direct experiht it necessary to rep at this experier scale, and by lass baloon (A Pl iv fig 4) with an opening three inches diaround with emery, and pierced with two holes for the tubes yyy, xxx Before shutting the baloon with its stopper, I introduced the support BC, surrs of phosphorus; the stopper was then fitted to the opening of the baloon, luted with fat lute, and covered with slips of linen spread with quick-lis: When the lute was perfectly dry, the weight of the whole apparatus was deterrain and a half I next exhausted the baloon, by means of an air puas bya stop cock adapted to it This kind of experiment is most readily and most exactly performed by means of the hydro-pneumatic machine described by Mr Meusnier and466

and explained in the latter part of this work, with several important additions and corrections since made to it by Mr Meusnier With this instrument we can readily ascertain, in the as introduced into the baloon, and the quantity consus were properly disposed, I set fire to the phosphorus with a burning glass The coht flae quantities of white flakes attached themselves to the inner surface of the baloon, so that at last it was rendered quite opake The quantity of these flakes at last becaas was continually supplied, which ought to have supported the co allowed the apparatus to cool coas ehed the baloon accurately, before it was opened I next washed, dried, and weighed the s in the cup, on purpose to determine the whole quantity of phosphorus consumed in the experiment; this residuum of the phosphorus was of a yellow ochrey colour It is evident, that by these several precautions, I could easily deterht of the flakes produced by the coen which had coave very nearly the same results with the for its combustion, had absorbed a little en; and I learned with ht of the new substance, produced in the experihts of the phosphorus consuen absorbed, which indeed was easily deteras employed be pure, the residuuas e escapes froen gas, and that the only action of the phosphorus is to separate the oxygen from the caloric, hich it was before united

I mentioned above, that when any combustible body is burnt in a hollow sphere of ice, or in an apparatus properly constructed upon that principle, the quantity of icethe combustion is an exact ed Upon this head, the iven by M de la Place andsubmitted the combustion of phosphorus to this trial, we found that one pound of phosphorusits combustion

The combustion of phosphorus succeeds equally well in atas, with this difference, that the coe proportion of azotic gas as, and that only about one-fifth part of the air eas only is absorbed, the proportion of the azotic gas becoreat toward the close of the experiment, as to put an end to the coed by coht, white, flakey matter; and its properties are entirely altered by this transfor insoluble in water, it becoreedy of moisture, as to attract the hu rapidity; by this means it is converted into a liquid, considerably ravity than water In the state of phosphorus before combustion, it had scarcely any sensible taste, by its union with oxygen it acquires an extremely sharp and sour taste: in a word, froed into an incombustible substance, and becomes one of those bodies called acids

This property of a combustible substance to be converted into an acid, by the addition of oxygen, we shall presently find belongs to a great nuic requires that we should adopt a co all these operations which produce analogous results; this is the true way to simplify the study of science, as it would be quite impossible to bear all its specifical details in the ed For this reason, we shall distinguish this conversion of phosphorus into an acid, by its union with oxygen, and in general every coen with a coenation_: froenate_, and of consequence shall say, that in _oxygenating_ phosphorus we convert it into an acid

Sulphur is likewise a combustible body, or, in other words, it is a body which possesses the power of decoen from the caloric hich it was combined This can very easily be proved, by iven with phosphorus; but it is necessary to premise, that in these operations with sulphur, the same accuracy of result is not to be expected as with phosphorus; because the acid which is formed by the combustion of sulphur is difficultly condensible, and because sulphur burns with asses But I can safely assert, froas; that the resulting acid is considerably heavier than the sulphur burnt; that its weight is equal to the suhts of the sulphur which has been burnt, and of the oxygen absorbed; and, lastly that this acid is weighty, incombustible, and miscible ater in all proportions: The only uncertainty reard to the proportions of sulphur and of oxygen which enter into the composition of the acid

Charcoal, which, fro it, must be considered as a simple coen gas, by absorbing its base fro from this combustion does not condense in the common temperature; under the pressure of our ate proportion of water to combine with or be dissolved in This acid has, however, all the known properties of other acids, though in a weaker degree, and combines, like the neutral salts

The coas, lass, (A Pl IV fig 3) placed over mercury: but, as the heat of red hot iron is not sufficient to set fire to the charcoal, we must add a small morsel of tinder, with a minute particle of phosphorus, in the same manner as directed in the experiment for the combustion of iron A detailed account of this experiment will be found in the memoirs of the academy for 1781, p 448 By that experiht of charcoal require 72 parts of oxygen for saturation, and that the aeriforht to the suas employed This aeriform acid was called fixed or fixable air by the chemists who first discovered it; they did not then knohether it was air rese that of the atmosphere, or some other elastic fluid, vitiated and corrupted by combustion; but since it is now ascertained to be an acid, forenation of its peculiar base, it is obvious that the na charcoal in the apparatus mentioned p 60, Mr de la Place and I found that one lib of charcoalthe coen were absorbed, and that 3 libs 9 oz 1 gros 10 grs of acid gas were forrain for each cubical inch, in the common standard temperature and pressure as are produced by the coht multiply these experiments, and show by a numerous succession of facts, that all acids are formed by the co so in place, by the plan which I have laid down, of proceeding only from facts already ascertained, to such as are unknown, and of drawing my examples only from circumstances already explained In the mean tiiving a clear and accurate conception of the manner in which acids are foren is an element common to them all, which constitutes their acidity; and that they differ froenated or acidified substance We uish between the acidifiable, base, which Mr de Morveau calls the radical, and the acidifiing principle or oxygen